X0306 4 2021-03-06 0 0001666134 BLACKLINE, INC. BL 0001688366 Partin Mark 21300 VICTORY BLVD 12TH FLOOR WOODLAND HILLS CA 91367 0 1 0 0 Chief Financial Officer Common Stock 2021-03-06 4 A 0 11230 0.00 A 105910 D Stock Option (right to buy) 111.53 2021-03-06 4 A 0 24470 0.00 A 2031-03-06 Common Stock 24470 24470 D Each share is represented by a Restricted Stock Unit ("RSU"). 25% of the RSUs will vest on the one (1) year anniversary of February 20, 2021 (the "Annual RSU Vesting Commencement Date"), and 1/16th of the RSUs will vest every three months thereafter on the same day of the month as the Annual RSU Vesting Commencement Date, subject to the Reporting Person's continued service through each applicable vesting date. 25% of the shares subject to the option will vest on the one (1) year anniversary of February 20, 2021 (the "Annual Option Vesting Commencement Date"), and 1/16th of the remaining shares subject to the option will vest every three months thereafter on the same day of the month as the Annual Option Vesting Commencement Date, subject to the Reporting Person's continued service through each applicable vesting date. /s/ Karole Morgan-Prager, Attorney-in-Fact 2021-03-08